Qiagen N.V, announced its support for the implementation of new guidelines presented by the World Health Organization (WHO) as part of its Post-2015 Global Tuberculosis Strategy (End TB). This strategy document outlines a 20-year blueprint and now includes new guidelines that address the management of latent tuberculosis. These new WHO guidelines promote for the first time the screening of specific vulnerable populations for latent TB infection and treating the infection to prevent progression to active TB disease, which currently kills 1.5 million people a year. The guidelines recommend programmatic intervention for more than 100 countries with an incidence below 100 cases per 100,000 population.
Qiagen will collaborate with international health institutions, non-governmental organisations and commercial partners to support implementation of the new WHO guidelines through awareness campaigns and educational programmes, improved access to QuantiFERON-TB Gold, research support and other collaborative efforts. QuantiFERON-TB Gold already is being adopted in many countries as the latent TB screening tool of choice, including the United States, Europe and Japan. QuantiFERON-TB Gold is replacing the century-old tuberculin skin test (TST), which requires at least two patient visits and often gives false-positive readings that lead to unnecessary follow-up evaluation and medical costs.
An estimated 9.0 million people worldwide had active TB disease in 2013 and 1.5 million died of the disease, according to WHO. While treatment efforts in the past two decades have reduced the death toll from the ongoing TB epidemic, the disease is still present and taking lives in all regions of the world. WHO is putting forward a broad strategy to end the global epidemic by 2035, reduce TB deaths by 95 per cent, cut active cases by 90 per cent, and eliminate the catastrophic economic burdens for TB-affected regions and households. The strategy outlines actions to strengthen TB treatment and prevention; mobilise resources; accelerate development of new drugs, vaccines and diagnostics; and reform social support.
For the first time, the WHO strategy calls on health authorities to confront the problem of latent TB infection (LTBI) a global pool of 2 billion people infected with Mycobacterium tuberculosis, who stand up to a 10 per cent chance of developing active, contagious TB disease in their lifetimes. The new WHO guidelines recommend screening the most at-risk populations, such as HIV-positive patients, young children and adults in contact with active TB patients, and immunocompromised patients, and providing preventive treatment to those considered at risk of active TB development. The guidelines invite TB control programs to consider screening other groups such as immigrants, prisoners and healthcare workers in high- and middle-income countries with an incidence of less than 100 per 100,000. The strategy also calls for more study of preventive treatment in a range of high-risk groups.
“The World Health Organization is advancing a bold strategy for action at all stages of the disease, and we applaud the drive to eliminate this devastating epidemic. We are pleased that WHO now advocates preventive screening for latent TB infection among the most at-risk populations in addition to measures to address active disease as described in previous guideline releases,” said Masae Kawamura, M.D., senior director, medical and scientific affairs QuantiFERON, for Qiagen. “Studies have shown that TB is a disease where measures directed towards the source, the latent TB infected population, are highly effective and efficient. We are working closely with public health authorities around the world to enhance TB control, including the screening and treatment of latent infection. Qiagen’s QuantiFERON-TB Gold is a more accurate, easier-to-handle alternative to the tuberculin skin test a modern approach for latent TB infection screening in an integrated TB control programme.”
Dr. Lee Reichman, M.P.H., executive director of the Global Tuberculosis Institute at the New Jersey Medical School at Rutgers University, added: “The post-2015 WHO strategy builds on the life-saving success of directly observed therapy and rightly integrates preventive actions such as screening and treating for latent TB infection. Preventing latent infection from progressing to active, contagious disease is crucial to achieving control, as well as preventing all of the downstream consequences of the disease such as death, debilitation and, importantly, multi-drug resistant disease. While resources are always a challenge, we can enhance effectiveness by targeting the groups most in need of testing and treatment: contacts of active cases, HIV-positive patients, healthcare workers, people in congregate settings like prisons or the military, and immunocompromised patients such as people with diabetes.”
QuantiFERON-TB Gold (QFT) is the industry-leading interferon-gamma release assay (or IGRA), a modern blood test that is faster, less labor-intensive and more accurate than the tuberculin skin test. A particular issue leading clinicians to adopt QuantiFERON-TB Gold is the high rate of false positives with the older TST technology, which often identifies 20-85 per cent of patients as infected when they are not. False-positive results require follow-up care such as physical examinations, x-rays and laboratory work, even for patients who turn out to have no TB infection adding unnecessarily to healthcare expenses.
In addition, QuantiFERON-TB Gold can reduce false-positive readings caused by common environmental mycobacteria exposure and by the Bacille Calmette-Guérin (BCG) vaccination, which newborns in many countries receive as a matter of policy. The WHO post-2015 strategy supports use of the BCG vaccine in high-burden countries. The TST is especially inaccurate in BCG-vaccinated persons because of cross-reacting antigens that cause false-positive results. QuantiFERON-TB Gold does not cross-react with the BCG vaccine, and positive readings with QuantiFERON-TB Gold are up to 99 per cent accurate.
Qiagen continues to pursue research and innovation to support tuberculosis control. The company is preparing for commercialisation of QuantiFERON-TB Gold Plus (QFT-Plus), an improved test for latent TB infection that will deliver a better clinical profile and further workflow optimisation. Qiagen also has engaged with the Max Planck Institute for Infection Biology on the analysis of biomarkers that can differentiate individuals with latent TB infection and patients with active TB.